Metamath Proof Explorer


Theorem upcic

Description: A universal property defines an object up to isomorphism given its existence. (Contributed by Zhi Wang, 17-Sep-2025)

Ref Expression
Hypotheses upcic.b
|- B = ( Base ` D )
upcic.c
|- C = ( Base ` E )
upcic.h
|- H = ( Hom ` D )
upcic.j
|- J = ( Hom ` E )
upcic.o
|- O = ( comp ` E )
upcic.f
|- ( ph -> F ( D Func E ) G )
upcic.x
|- ( ph -> X e. B )
upcic.y
|- ( ph -> Y e. B )
upcic.z
|- ( ph -> Z e. C )
upcic.m
|- ( ph -> M e. ( Z J ( F ` X ) ) )
upcic.1
|- ( ph -> A. w e. B A. f e. ( Z J ( F ` w ) ) E! k e. ( X H w ) f = ( ( ( X G w ) ` k ) ( <. Z , ( F ` X ) >. O ( F ` w ) ) M ) )
upcic.n
|- ( ph -> N e. ( Z J ( F ` Y ) ) )
upcic.2
|- ( ph -> A. v e. B A. g e. ( Z J ( F ` v ) ) E! l e. ( Y H v ) g = ( ( ( Y G v ) ` l ) ( <. Z , ( F ` Y ) >. O ( F ` v ) ) N ) )
Assertion upcic
|- ( ph -> X ( ~=c ` D ) Y )

Proof

Step Hyp Ref Expression
1 upcic.b
 |-  B = ( Base ` D )
2 upcic.c
 |-  C = ( Base ` E )
3 upcic.h
 |-  H = ( Hom ` D )
4 upcic.j
 |-  J = ( Hom ` E )
5 upcic.o
 |-  O = ( comp ` E )
6 upcic.f
 |-  ( ph -> F ( D Func E ) G )
7 upcic.x
 |-  ( ph -> X e. B )
8 upcic.y
 |-  ( ph -> Y e. B )
9 upcic.z
 |-  ( ph -> Z e. C )
10 upcic.m
 |-  ( ph -> M e. ( Z J ( F ` X ) ) )
11 upcic.1
 |-  ( ph -> A. w e. B A. f e. ( Z J ( F ` w ) ) E! k e. ( X H w ) f = ( ( ( X G w ) ` k ) ( <. Z , ( F ` X ) >. O ( F ` w ) ) M ) )
12 upcic.n
 |-  ( ph -> N e. ( Z J ( F ` Y ) ) )
13 upcic.2
 |-  ( ph -> A. v e. B A. g e. ( Z J ( F ` v ) ) E! l e. ( Y H v ) g = ( ( ( Y G v ) ` l ) ( <. Z , ( F ` Y ) >. O ( F ` v ) ) N ) )
14 1 2 3 4 5 6 7 8 9 10 11 12 13 upciclem4
 |-  ( ph -> ( X ( ~=c ` D ) Y /\ E. r e. ( X ( Iso ` D ) Y ) N = ( ( ( X G Y ) ` r ) ( <. Z , ( F ` X ) >. O ( F ` Y ) ) M ) ) )
15 14 simpld
 |-  ( ph -> X ( ~=c ` D ) Y )